| 摘要 |
PURPOSE:To surely identify between a transmitting side input signal and a mediation signal by transmitting alarm indication signal information as multiplexing it at a transmitting side, and extracting the alarm indication signal information at a receiving side, and performing the switching control of a reception signal and an alarm indication signal according to this information. CONSTITUTION:At the transmitting side A, a mediation signal generation circuit 3 generates and outputs the mediation signal (c). Then, the output of a logical switching circuit 4 and the alarm indication signal information (b) are multiplexed by a multiplexing circuit 5, and are sent to a radio circuit. On the other hand, at the receiving side B, the transmitted multiplexed signal is separated into a separated output signal (g) and the alarm indication signal information (h) by a demultiplexing circuit 6. Then, an alarm indication signal generation circuit 9 generates the alarm indication signal (f), and outputs it to the logical switching circuit 10. The logical switching circuit 10 is controlled by the above-mentioned signal information (h) and performs switching. Accordingly, even if the input signal (a) is similar to the mediation signal (c), they can be surely identified. |
